<template>
  <div>
    <span>全选:</span>
    <input type="checkbox" v-model="isAll" />
    <button @click="choose">反选</button>
    <ul>
      <li v-for="item in arr" :key="item.name">
        <input type="checkbox" v-model="item.c" />
        <span>{{ item.name }}</span>
      </li>
    </ul>
  </div>
</template>

<script>
export default {
  data () {
    return {
      arr: [
        {
          name: '猪八戒',
          c: false
        },
        {
          name: '孙悟空',
          c: false
        },
        {
          name: '唐僧',
          c: false
        },
        {
          name: '白龙马',
          c: false
        }
      ]
    }
  },
  computed: {
    isAll: {
      get () {
        return this.arr.every(item => item.c)
      },
      set (val) {
        this.arr.forEach(item => {
          item.c = val
        })
      }
    }
  },
  methods: {
    choose () {
      this.arr.forEach(item => {
        item.c = !item.c
      })
    }
  }
}
</script>
